The present embodiments relate to imaging of glass products and glass containers for determining the quality of the glass product for flame polishing.
Glass manufacturers for various products confront increased quality demands for the products, especially in art and tableware, container glass, flacons (eg, high quality bottles for products such as for example perfume) and also in the flat glass segment. In conjunction with the rise in quality demands, glass manufacturers are encouraged to cut production costs and to increase glass production efficiency, such as for example replacing acid polishing and the minimization/elimination of mechanical post-processing during glass surface treatment.
Certain technologies and processes have been produced to provide a higher quality product and productivity efficiencies. Process parameters of the burner technologies, such as flow velocities and heat transfer rates, working distance of the burners, flame shapes, etc., enhance the efficiency of glass surface treatment as well as fire polishing and related processes.
For example, HYDROPOX™ and HYDROPOX-C™ burner systems distributed by Linde Aktiengesellschaft of Germany use increased thermal efficiencies of pre-mixing burner technologies to improve the heat transfer rate due to a higher flow velocity of the burner technologies and a shorter distance of the burners from the product. The heat transfer rates of pre-mixed hydrogen/oxygen flames are approximately two to three times greater than those of pre-mixed natural gas/oxygen flames. Similarly, the heat transfer rates of pre-mixed natural gas/oxygen and hydrogen/oxygen flames are approximately six to eight times greater than the heat transfer rates of post-mixing burners with the same mediums.
However, the use of these technologies are a relatively expensive, and such processes are usually reserved for use with premium glass products. Additionally, due to the significant differences in shape of the products, there is frequently little or no repetition of set-up for these premium products and each run for the products is usually set up manually, which also increases the cost of the process. In certain applications for premium products, the amount of time in the glass leher (i.e., the heat treatment annealing stage) can be as high as 40 to 180 minutes, which results in a large amount of premium product being processed before there is any feedback of quality in the resulting processed product. Glass bottle forming machines typically have more than one mold and in some cases up to 12 sections with each section having from one to four molds for the products to be processed. Therefore, depending upon the position of the mold with respect to other ones of the mold in the machine, the temperature of the glass may be different from the first mold to the very last mold processed. Consequently, if burners are positioned too close to the product and/or operated under excessive fire power, there is a risk that flashbacks will occur and/or the flame arresters being blown out which will stop the flame polishing process, thereby requiring replacement of components, pressure testing and then re-ignition of the melter. This results in a tremendous loss of production time and product loss.
It would therefore be desirable to know the quality of the glass for premium products prior to the run being completed so that the necessary adjustments can be made during the production run, such as in HYDROPOX™ and HYDROPOX-C™ systems.